Changeset 37730 in webkit for trunk/JavaScriptCore/VM/CodeGenerator.cpp

Timestamp:

Oct 20, 2008, 9:48:30 AM (17 years ago)

Author:

[email protected]

Message:

JavaScriptCore:

2008-10-20 Geoffrey Garen <​[email protected]>

Reviewed by Darin Adler.

Fixed ​https://bugs.webkit.org/show_bug.cgi?id=21735
Emit profiling instrumentation only if the Web Inspector's profiling
feature is enabled

22.2% speedup on empty function call benchmark.
2.9% speedup on v8 benchmark.
0.7% speedup on SunSpider.

Lesser but similar speedups in bytecode.

• VM/CTI.cpp: (JSC::CTI::compileOpCall): (JSC::CTI::privateCompileMainPass): (JSC::CTI::privateCompileSlowCases): Nixed JITed profiler hooks. Profiler hooks now have their own opcodes. Added support for compiling profiler hook opcodes.

(JSC::CodeBlock::dump): Dump support for the new profiling opcodes.

• VM/CodeGenerator.h:
• VM/CodeGenerator.cpp: (JSC::CodeGenerator::CodeGenerator): (JSC::CodeGenerator::emitCall): (JSC::CodeGenerator::emitConstruct): Conditionally emit profiling hooks around call and construct, at the call site. (It's easier to get things right this way, if you have profiled code calling non-profiled code. Also, you get a slightly more accurate profile, since you charge the full cost of the call / construct operation to the callee.)

Also, fixed a bug where construct would fetch the ".prototype" property
from the constructor before evaluating the arguments to the constructor,
incorrectly allowing an "invalid constructor" exception to short-circuit
argument evaluation. I encountered this bug when trying to make
constructor exceptions work with profiling.

• VM/Machine.cpp: (JSC::Machine::callEval): Removed obsolete profiler hooks.

(JSC::Machine::throwException): Added a check for an exception thrown
within a call instruction. We didn't need this before because the call
instruction would check for a valid call before involing the profiler.
(JSC::Machine::execute): Added a didExecute hook at the end of top-level
function invocation, since op_ret no longer does this for us.

(JSC::Machine::privateExecute): Removed obsolete profiler hooks. Added
profiler opcodes. Changed some ++vPC to vPC[x] notation, since the
latter is better for performance, and it makes reasoning about the
current opcode in exception handling much simpler.

(JSC::Machine::cti_op_call_NotJSFunction): Removed obsolete profiler
hooks.

(JSC::Machine::cti_op_create_arguments_no_params): Added missing
CTI_STACK_HACK that I noticed when adding CTI_STACK_HACK to the new
profiler opcode functions.

(JSC::Machine::cti_op_profile_will_call):
(JSC::Machine::cti_op_profile_did_call): The new profiler opcode
functions.

(JSC::Machine::cti_op_construct_NotJSConstruct): Removed obsolete profiler
hooks.

• VM/Machine.h: (JSC::Machine::isCallOpcode): Helper for exception handling.

• VM/Opcode.h: Declare new opcodes.

• kjs/JSGlobalObject.h: (JSC::JSGlobalObject::supportsProfiling): Added virtual interface that allows WebCore to specify whether the target global object has the Web Inspector's profiling feature enabled.

• profiler/Profiler.cpp: (JSC::Profiler::willExecute): (JSC::Profiler::didExecute): (JSC::Profiler::createCallIdentifier):
• profiler/Profiler.h: Added support for invoking the profiler with an arbitrary JSValue*, and not a known object. We didn't need this before because the call instruction would check for a valid call before involing the profiler.

WebCore:

2008-10-18 Geoffrey Garen <​[email protected]>

Reviewed by Darin Adler.

Fixed ​https://bugs.webkit.org/show_bug.cgi?id=21735
Emit profiling instrumentation only if the Web Inspector's profiling
feature is enabled

• bindings/js/JSDOMWindowBase.cpp: (WebCore::JSDOMWindowBase::supportsProfiling):
• bindings/js/JSDOMWindowBase.h: Implemented the interface for specifying whether a target global object has the Web Inspector's profiling feature enabled.

• inspector/JavaScriptDebugServer.cpp: (WebCore::JavaScriptDebugServer::recompileAllJSFunctionsSoon): (WebCore::JavaScriptDebugServer::didAddListener): (WebCore::JavaScriptDebugServer::didRemoveListener):
• inspector/JavaScriptDebugServer.h: Exported an API for recompiling, used by the Settings object.

• page/Settings.cpp: (WebCore::Settings::Settings): (WebCore::Settings::setDeveloperExtrasEnabled):
• page/Settings.h: Recompile when the developer menu is enabled/disabled for the first time, to add/remove profiling hooks. In the future, with better Web Inspector UI, we can do this on a page-by-page basis, instead of a global basis.

LayoutTests:

2008-10-18 Geoffrey Garen <​[email protected]>

Reviewed by Darin Adler.

Test for bugs fixed while working on ​https://bugs.webkit.org/show_bug.cgi?id=21735
Emit profiling instrumentation only if the Web Inspector's profiling
feature is enabled

• fast/js/exception-thrown-from-new-expected.txt: Added.
• fast/js/exception-thrown-from-new.html: Added.

File:

• trunk/JavaScriptCore/VM/CodeGenerator.cpp (modified) (8 diffs)

trunk/JavaScriptCore/VM/CodeGenerator.cpp

@@ -196 +196 @@
 CodeGenerator::CodeGenerator(ProgramNode* programNode, const Debugger* debugger, const ScopeChain& scopeChain, SymbolTable* symbolTable, CodeBlock* codeBlock, VarStack& varStack, FunctionStack& functionStack)
     : m_shouldEmitDebugHooks(!!debugger)
+    , m_shouldEmitProfileHooks(scopeChain.globalObject()->supportsProfiling())
     , m_scopeChain(&scopeChain)
     , m_symbolTable(symbolTable)
@@ -274 +275 @@
 CodeGenerator::CodeGenerator(FunctionBodyNode* functionBody, const Debugger* debugger, const ScopeChain& scopeChain, SymbolTable* symbolTable, CodeBlock* codeBlock)
     : m_shouldEmitDebugHooks(!!debugger)
+    , m_shouldEmitProfileHooks(scopeChain.globalObject()->supportsProfiling())
     , m_scopeChain(&scopeChain)
     , m_symbolTable(symbolTable)
@@ -343 +345 @@
 CodeGenerator::CodeGenerator(EvalNode* evalNode, const Debugger* debugger, const ScopeChain& scopeChain, SymbolTable* symbolTable, EvalCodeBlock* codeBlock)
     : m_shouldEmitDebugHooks(!!debugger)
+    , m_shouldEmitProfileHooks(scopeChain.globalObject()->supportsProfiling())
     , m_scopeChain(&scopeChain)
     , m_symbolTable(symbolTable)
@@ -1159 +1162 @@
         callFrame.append(newTemporary());
 
+    if (m_shouldEmitProfileHooks) {
+        emitOpcode(op_profile_will_call);
+        instructions().append(func->index());
+    }
+
     emitExpressionInfo(divot, startOffset, endOffset);
     m_codeBlock->structureIDInstructions.append(instructions().size());
@@ -1168 +1176 @@
     instructions().append(argv.size()); // argc
     instructions().append(argv[0]->index() + argv.size() + RegisterFile::CallFrameHeaderSize); // registerOffset
+
+    if (m_shouldEmitProfileHooks) {
+        emitOpcode(op_profile_did_call);
+        instructions().append(func->index());
+    }
+
     return dst;
 }
@@ -1193 +1207 @@
     ASSERT(func->refCount());
 
-    // Load prototype.
-    emitExpressionInfo(divot, startOffset, endOffset);
     RefPtr<RegisterID> funcProto = newTemporary();
-    emitGetById(funcProto.get(), func, globalData()->propertyNames->prototype);
 
     // Generate code for arguments.
@@ -1206 +1217 @@
     }
 
+    if (m_shouldEmitProfileHooks) {
+        emitOpcode(op_profile_will_call);
+        instructions().append(func->index());
+    }
+
+    // Load prototype.
+    emitExpressionInfo(divot, startOffset, endOffset);
+    emitGetById(funcProto.get(), func, globalData()->propertyNames->prototype);
+
     // Reserve space for call frame.
     Vector<RefPtr<RegisterID>, RegisterFile::CallFrameHeaderSize> callFrame;
@@ -1224 +1244 @@
     instructions().append(dst->index());
     instructions().append(argv[0]->index());
+
+    if (m_shouldEmitProfileHooks) {
+        emitOpcode(op_profile_did_call);
+        instructions().append(func->index());
+    }
 
     return dst;